Surface active agent compositions

ABSTRACT

A BIODEGRADABLE SURFACE ACTIVE COMPOSITION THAT DOES NOT IRRITATE THE EYES COMPRISING AN AQUEOUS SOLUTION OF A COMPOUND HAVING THE FORMULA   R-CO-NH-(CH2CH2O)2-SO2M   IN WHICH R IS AN ALKYL OR ALKENYL GROUP AND M IS A CATION.

United States Patent Office 3,562,170 Patented Feb. 9, 1971 Int. Cl.Clld 1/12 US. Cl. 252-152 Claims ABSTRACT OF THE DISCLOSURE Abiodegradable surface active composition that does not irritate the eyescomprising an aqueous solution of a compound having the formula RCO-NH(CH CH O SO M in which R is an alkyl or alkenyl group and M is a cation.

This application is a continuation-in-part of application 525,345 filedFeb. 7, 1966, which has been abandoned.

SUMMARY OF THE INVENTION A number of known surface-active agents areused as ingredients in shampoos for the hair.

A first category of such known surface-active agents comprises thesulfates of fatty alcohols, in the form of the alkali salts, such assodium, ammonium, etc., in which the fatty alkyl remainder, hereinafterdesignated by R, comprises 12-18 carbon atoms. These sulfates mayrespond to one of the two formulas ROSO M or according to whether theproduct is or is not oxyethylenated. (In the formulas n is a number from1 to 4 and M is a cation, such as sodium, potassium, ammonium, etc.) Theproducts falling in this category have excellent detergent qualities,but they irritate the skin and mucous membranes, and their use makes thehair feel rough after shampooing.

A second category of known surface-active agents comprises the sulfatedamides, which have the great advantages that their use imparts anagreeable feel to the hair after shampooing and they are less irritatingto the skin and mucous membranes. However, the sulfated amidesheretofore known tend to hydrolyze after a few days in solution, so thatit is necessary to prepare the solution containing them just before use.These sulfated amides are therefore suitable only for use in powders,and not for use in shampoos sold in solution form.

The objects of the present invention is to avoid the disadvantages ofthe sulfate of fatty alcohols, i.e., the tendency to irritate the skinand the undesirable feel with which the hair is left after shampooing,without accepting the lack of stability in solution which ischaracteristic of the known sulfated amides.

The present invention is therefore directed to the new article ofmanufacture which is an anionic surface-active agent in the form of anamide sulfate having the following formula:

in which R is a linear or branched chain alkyl or alkenyl, having from11 to 26 and preferably 11-17 carbon atoms, and M is an alkali metal,alkaline earth metal, ammonium, or a short-chain mono, di or trialkyl-ammonium or alkylol ammonium.

A further object of the present invention is to provide new cosmeticcompositions containing, preferably in aqueous solution, at least onecomposition responding to Formula I, these compositions being especiallyuseful for shampooing the hair. It is clear that these compositions maycontain other products and additives conventionally used in cosmeticssuch as thickening agents, other ionic or nonionic surface activeagents, etc.

Surprisingly, it has been found that compositions containing thecompounds of Formula I are particularly resistant to hydrolysis so thatthey may be used in the manufacture of shampoos to be sold as aqueoussolutions. It should be noted that the hydrolysis stability of the amidesulfates of this invention cannot be predicted from the stability of thecorresponding amide because an amide may be stable to hydrolysis eventhough its sulfates are unstable.

The cosmetic compositions of this invention generally contain from 5 to20%, and preferably about 10% by weight of the compounds of Formula I.The pH of these compositions may be between 6 and 9 and preferably about7. These compositions at this concentration and pH range will nothydrolyze and will not irritate the skin and mucous membranes of theeyes.

The perfect stability of these compounds against hydrolysis isparticularly well demonstrated by the following tests:

The quantities of an amide sulfate representative of the present stateof the art (specifically, the sodium salt of the sulfuric ester of themono-ethanolamide of copra), and of an amide sulfate of this invention,which hydrolyzed as a function of time have been studied. The two amidesulfates studied were tested in a 1% aqueous solution at a pH of 9 and atemperature of 75 C. The method of measurement was that described byDesnuelle and Micaelli in the periodical Oleagineux, No. 6, 1949, onpages 353-357 and 720-725. The results are summarized in the followingtable:

Test on ROONH- (CH2CH20)2SO3N3 with R an alkyl radical derived fromcopra and n=2 Test on RCONH C 2C 2-OSOsNa with R an alkyl radical Timein hours derived from copra and n=1 A B A B in 6 hours, whereas theamide sulfate of this invention remains substantially unchanged.

The compositions of this invention, when used in shampoos, impart anagreeable feel to the hair, and they do not irritate the mucousmembranes, especially those of the eye, a fact which has been verifiedby tests on the eyes of live rabbits. These compositions are alsoreadily bio-degradable.

Another object of the present invention is to provide a method ofpreparing compositions containing the compounds of Formula I essentiallycharacterized by the fact that a fatty acid, such as one derived fromcopra, having the formula R-COOH, in which formula R designates an alkylor alkenyl group having 11-26 carbon atoms is reacted withdi-glycolamine and the alcohol function of the amide thus obtained issulfated. The sulfation step may be followed by salification or thesalification may occur concurrently.

This process may be carried out in several different ways.

The first step of the process, which consists in obtaining the amideitself may be carried out in any of the following illustrative ways:

(a) By condensation of a single fatty acid or a fatty acid mixturederived from copra having the formula RCOOH with diglycolamine at atemperature of the order of 160 C. to 200 C., eliminating any water.

(b) By aminolysis of an ester of a fatty acid, for example, a methyl orethyl ester of a fatty acid, eliminating the corresponding alcohol, theaminolysis reaction being preferably carried out in the presence of aknown catalyst. The glycerides may also be used to make the compounds ofFormula I by this method.

(c) Beginning with a fatty acid chloride.

The second step of the process, which consists of sulfating the amideobtained in the first step, may also be carried out in several differentillustrative ways, particularly:

(a) By using sulfamic acid. This method has the advantage of yieldingthe ammonium salts immediately, so that it is not necessary to salify asulfonic acid function after the sulfation, at the risk of forming amineral salt in the resulting product. The resulting ammonium salt maybe used directly in aqueous solution. If the ammonia is eliminated byheating, amine salts may be obtained, particularly alkylolamine salts,and if desired, salts of alkali metals.

(b) By using sulfuric acid. In this case sulfuric acid is added slowlyto the melted amide in a mixing device which is vigorously actuated. Anapproximately 100% excess quantity of the sulfating agent is used. Thefluidity of the reaction medium may be increased by adding ahydrosoluble solvent. After having determined that the reaction has beencompleted, using a test of solubility in an aqueous medium, the sulfatedproduct is neutralized by pouring it into a mixture of carbonate andbicarbonate of soda. The end product is powder.

(c) By using chlorosulfonic acid. This step is carried out in achlorinated solvent, such as chloroform, at a temperature of 2S C. Thehydrochloric acid formed is drawn off by a current of inert gas or byuse of a slight vacuum. After elimination of the solvent, the sulfatedproduct may be neutralized with soda, ammonia, or with alkylolaminessuch as ethanolamine or isopropanolamine to form the desired salt.

In order to further illustrate the invention a method of preparing theammonium salt of the sulfuric ester of the diglycolamide of the acids ofcopra will now be described, and several examples will be given showingthe use of the compositions responding to Formula I as ingredients forshampoos. Similar results are obtained by forming the sodium, potassium,and alkylamine salts and by using unmixed fatty acids as the startingmaterial to form unmixed salts.

EXAMPLE 1 Preparation of the ammonium salt of the sulfuric ester of thediglycolamide of the acids of copra.

(a) Preparation of N-acyl(copra)-diglycolamine A mixture of 207 grams ofthe fatty acids of copra and 112 grams of diglycolamine are heated andagitated under a nitrogen atmosphere to a temperature of 170- 180 C.,distilling off the water formed in the course of the reaction.

After three hours of heating 97% of the fatty acids introduced arecondensed with the diglycolamine. After 7 hours of heating thepercentage of condensation is 98.3%. The product obtained is in the formof a white waxy mass melting at C.

4 (b) Sulfation of N acyl(copra) diglycolamine with sulfamic acid 20grams of sulfamic acid and 5 grams of urea are added to 59 grams ofmelted N-acyl(copra)-diglycolamine. The mixture is vigorously agitatedwhile being heated to 120 C. The reaction mixture thickens rapidly assulfation progresses, and the process is completed in a few minutes.

After cooling a yellowish waxy product is obtained, which dissolvesreadily in water and is the ammonium salt of sulfuric ester of thediglycolamide of the acids of copra.

EXAMPLE 2 The following mixture is prepared: Solution containing 26.8%of Sulfuric ester of the diglycol amide of copra acids, am-

monium salt-40 g.

Laurie diethanolamide4 g.

Water, q.s.p.--l00 cm.

EXAMPLE 3 The following mixture is prepared: Solution containing 26.8%of- Sulfuric ester of the diglycolamide of copra acids, am-

monium salt-20 g.

Ammonium lauryl sulfate-l5 g.

Laurie diethanolamideIlS g.

Water, q.s.p. cm.

EXAMPLE 4 The following mixture is prepared: Solution contain in g26.8%-

Sulfuric ester of the diglycolamide of copra acids, am-

monium salt-25 g.

Polyoxyethylene lauric alcohol having 12 molecules of ethylene acid-5 g.

Laurie diethanolamide4 g.

Water, q.s.p.-100 cm.

The composition described in each of Examples 2-4, when used as ashampoo, have good detergent properties, and produce plenty of foamhaving an agreeable consistency. After shampooing with the product thehair is glossy, bright, and feels soft to the touch.

The RCO group in Formula I may be derived from the followingillustrative fatty acids caprylic acid, capric acid, lauric acid,myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid,pelargonic acid, undecylic acid (10- undeceneoic acid).

From a commercial-standpoint the RC0 group in Formula I may also beobtained from mixtures of fatty acids obtained from oils and fats ofanimal or plant origin such as palm, cabbage palm, tallow, etc.

The RCO group may also be obtained from isoacids having the generalformula:

(HI-(CH2) r-C O OH and the antiisoacids having the general formula:

in which n is between 14 and 22 and 12 and 22 respectively. These acidscan be prepared in the form of a mixture for saponification fromlanolin.

The mixture of fatty acids prepared under the designation isostearicacid according to U.S. Pat. 2,812,342.

Fatty ramified acids sold under the name of neoacids as for example theneo-tridecanoic acid having the formula:

in which R is hydrocarbon radical containing 9 carbon atoms. Theseneoacids can be transformed according to the known methods withdiglycolamine to sulfatable hydroxyl amides.

Illustrative salts include those in which M in Formula I is:

l) alkaline ions: such as Na, K, etc. NH4 (3) an alkylol ammonium suchas:

(a) HaN-OHzCHgOH (b) HaiL-CHzCHOHCH GH2OH2OH (c) HzN CHzCHzOH CHzCHOHCH3(d) H2N CHzGHOHCHa CHzOHzOH (e) HNCH2CH2OH CH CHOHCHg (I) H-CH2CIIOHCH3CH2CHOHCH3 (4) alkyl ammonium, such as:

HrN CHJCH;

CH HzN H CH3 4;)

CH2OH3 HNCH2CH3 CHzCH (5) Alkaline earth metal ions, such as calcium andmagnesium.

Illustrative compounds of the invention include: 1 C H CONH(CH CI-l O)SO Na [C14H29CONH) 2503] 2C3. (3) C13H27CONH CH2CH20 SO NH 4) C HCONH(CH CH O) SO NH (5 C H CONH(CH CH O) SO NH C H (6)C13H27CONH(CH2CH2O)2SO3NH2(C2H3)2 (7) C H CONH (CH CH O SO NH (CH 3 (8)C H CONH(CH CH O) SO NH (CH CH OH) (9) C H CONH(CH CI-I O) SO NH (CHCHOHCH (10) C13H27CONH(CH2CH20)2SO3NH(CH2CH2OH) 3 We have found that thecompositions which contain lauric and myristic acid derivatives andmixtures containing at least 50% of these acids have the best foamingcharacteristics.

EXAMPLE 5 The following comparative test was made to further show theadvantages of using the following method to obtain the compounds of thisinvention in which 12:2:

We prepared, using the method of this invention, lauric diglycolamidehaving the following formula:

C H CONHCH CH OCH CH OH (A) and the compound:

C H CONHCH CH O(CH CH O),,H (B) in which n has a statisticalaverageavalue of 1.

Compound A was prepared by the aminolysis of methyl laurate usingdiglycolamine (H NCI-l CH OCH CH OH) in excess of the required, thereactive mixture being progressively heated 7 up to 160 C. to eliminatethe methanol. The excess of diglycolamine was then evaporated undervacuum. The product thus obtained was recrystallized in the ethylacetate.

Compound B was prepared by condensing ethylene oxide on lauricmonoethanolamide (C H CONHCH CH OH) which was obtained by aminolysis ofmethyl laurate with monoethanolamine. Its melting point afterrecrystallization was 85 C.

The condensation of ethylene oxide is effected in the following fashion:

To 75 g. of lauryl monoethanolamine, add 3.5 g. of a methanol solutioncontaining 24.8% CH ONa. The CH ONa is eliminated under vacuum. In 73.3g. of the mixture thus obtained, heated to 0., pass the ethylene oxideafter having purged the equipment with nitrogen. In 45 minutes ofreaction at 135 to C., condensed 12.8 g. of ethylene oxide being 0.96mole per mole of ethanolamine. The product of condensation is ayellow-white wax having a hydroxyl index of 207.

We made a gas phase chromatography, after silicylation, using the methodof Sufiis et al. (J. Soc. Cosm.

Chemists, 76, 783-794 (1965). The condensation product contains thecompounds C H CONHCH CH OH and C H CONHCH CH OCH CH OH in approximatelyequal proportions.

Results.-This comparative test shows that the prior art composition (B)is a mixture containing a high proportion of monoethanolamides whichform sulfate derivatives that are unstable and hydrolyze. One couldlessen the proportion of monoethanolamides by augmenting the rate ofcondensation of ethylene oxide, but in this case, the products obtainedwould be less active because of their excessive hydrophile character.

The reaction of diglycolamine and diglycolamide avoids thesedisadvantages because the degree of condensation n==2 is alreadypresent. In contrast to this in the methods already known, thecondensation of ethylene acid on the monoethanolamide the degree ofcondensation of the group (CH CH O) is only a mean statistical value andthe product (B) is in reality a mixture in which a great proportion ofthe ethanolamides are not oxyethylenated and they hydrolyze.

The compounds in which n=2 all produce desirable foams. The compounds inwhich n=3 or more are not foaming agents. Compositions in which n is avariety of values but statistically equal to 2 tend to hydrolyze,irritate the eyes and do not produce desirable foams.

EXAMPLE 6 Preparation of ammonium and magnesium sulfate salts ofdodecanoyl amido ethoxy ethanol having the formula: C H CONHCH -CH -0CHCH OH The hydroxylated amide is prepared by aminolysis of methyl lauratewith diglycolamine in excess of 100% required for a complete reaction,the mixture is progressively heated up to C. to eliminate the methanol.The excess diglycolamine is then evaporated under vacuum. The product isthen recrystallized in ethyl acetate.

This compound is then sulfated with sulfamic acid according to theconditions which were given in Example 1.

50 g. of this sulfated product was dissolved in 150 ml. of water; tothis solution is added 2.25 g. of pulverized and sifted magnesium oxide,a little at a time, then it is heated to the boiling point to remove theammonia.

After 24 hours in a heated water bath the mixture is filtered to removethe unreacted magnesium oxide, 59% of the ammonium salt was transformedto the magnesium salt.

One obtains a solution which has good foaming properties.

EXAMPLE 7 Preparation of the magnesium salt of dodecanoyl sulfate amidoethoxy ethanol in the form of a powder.

Dissolve 57.4 g. of dodecanoyl amido ethoxy ethanol in 100 ml. ofchloroform. Cool this solution to 150 C., add drop by drop 25.6 g. ofsulfuric chlorohydrin maintaining the temperature below 25 C., understrong agitation over a 20 minute period. The reaction mixture stood atambient temperature for 1 hour under agitation then, in order toeliminate the hydrochloric acid, we passed nitrogen through the productunder reduced pressure.

The sulfatation product was neutralized in the following manner:

Milk of magnesia was prepared by dispersing 8 g. of magnesia in 20 ml.of water. This dispersion of magnesia was added under agitation to thechloroform solution of the sulfatation product. After one and one-halfhours, the mixture having then a very acid reaction, we added 2 g. ofpulverized magnesium. The mixture was left for one night, then wefiltered the excess magnesia. The chloroform and water were evaporated.The yield was 80%. The residue was put in acetone and the magnesium saltprecipitated. It was separated easily by filtration. This compound,after drying, is a white solid that can be pulverized. It dissolves veryeasily in water to form a foaming solution.

It will be appreciated that the foregoing examples have been givenpurely by way of illustration, and may be modified as to detail withoutdeparting from the basic principles of the invention as defined by thefollowing claims.

Particularly the composition of the present invention containsconventional shampoo ingredients choosed among the following:

Cetyl trimethyl ammonium bromide, lactic acid, diethanolamide of copra,polyethylene glycol, stearylic alcohol, paraffin oil, glycerin, ammoniumlauryl sulphate, lauric. diethanolamide, triethanolamide laurylsulphate,

carboxymethyl cellulose, oxyethylated lauric alcohol (12 mol. ethyleneoxide), glycerol mono stearate, etc.

What is claimed is:

1. A surface active composition consisting essentially of an aqueoussolution consisting essentially of a surface activating amount of anamide sulfate surface active agent having the formula RCONH(CH CH O -SOM in which R is selected from the group consisting of alkyl and alkenylgroups having 11 to 17 carbon atoms, and M is an ion selected from thegroup consisting of alkali metals, alkaline earth metals, ammonium,alkylammonium, and alkylolammonium, having a pH of about 6 to 9.

2. A method for shampooing hair comprising shampooing the hair with aneffective amount of the composition of claim 1.

3. A shampoo composition comprising the composition of claim 1 whichalso contains a compound selected from the group consisting of cetyltrimethyl ammonium bromide, lactic acid, diethanolamide of copra,polyethylene glycol, stearylic alcohol, paraffin oil, glycerin, ammoniumlauryl sulphate, lauric diethanolamide, triethanolamide lauryl sulphate,carboxymethyl cellulose, oxyethylated lauric alcohol (12 mol. ethyleneoxide) and glycerol mono stearate.

4. The composition of claim 1, wherein the amide sulfate surface activeagent is the only surface active agent present.

5. The composition of claim 4, wherein R is C H 6. The composition ofclaim 4, wherein R is C H 7. The composition of claim 4, wherein R isderived from copra.

8. The composition of claim 4, which contains 5 to 20% by weight of saidsurface active agent.

9. The composition of claim 4, wherein M is NH 10. A method ofshampooing hair comprising shampooing the hair with a shampooing amountof the composition of claim 4.

References Cited FOREIGN PATENTS 1,468,219 3/1967 France 260-401 LEON D.ROSDOL, Primary Examiner M. HALPERN, Assistant Examiner US. Cl. X.R.

